Question: $-3kl + 5l + 6m - 9 = 4l + 5m + 4$ Solve for $k$.
Answer: Combine constant terms on the right. $-3kl + 5l + 6m - {9} = 4l + 5m + {4}$ $-3kl + 5l + 6m = 4l + 5m + {13}$ Combine $m$ terms on the right. $-3kl + 5l + {6m} = 4l + {5m} + 13$ $-3kl + 5l = 4l - {m} + 13$ Combine $l$ terms on the right. $-3kl + {5l} = {4l} - m + 13$ $-3kl = -{l} - m + 13$ Isolate $k$ $-{3}k{l} = -l - m + 13$ $k = \dfrac{ -l - m + 13 }{ -{3l} }$ Swap the signs so the denominator isn't negative. $k = \dfrac{ {1}l + {1}m - {13} }{ {3l} }$